28238231 has 8 divisors (see below), whose sum is σ = 32313120. Its totient is φ = 24173568.

The previous prime is 28238201. The next prime is 28238233. The reversal of 28238231 is 13283282.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 28238231 - 2¹⁴ = 28221847 is a prime.

It is a super-2 number, since 2×28238231² = 1594795380018722, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 28238194 and 28238203.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28238233) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4775 + ... + 8903.

It is an arithmetic number, because the mean of its divisors is an integer number (4039140).

Almost surely, 2^28238231 is an apocalyptic number.

28238231 is a deficient number, since it is larger than the sum of its proper divisors (4074889).

28238231 is an equidigital number, since it uses as much as digits as its factorization.

28238231 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5113.

The product of its digits is 4608, while the sum is 29.

The square root of 28238231 is about 5313.9656566448. The cubic root of 28238231 is about 304.5176681643.

The spelling of 28238231 in words is "twenty-eight million, two hundred thirty-eight thousand, two hundred thirty-one".